Improvement in burglar-alarms



A. REIMS. Burglar-Alarm.

. No. 217,556. Patented July 15, 1879.-

WITNESSES f INVEJVTOR www 1 4'UNTTETD STATES PATENT @Enron .AUSTIN P. SIMS, OF NASHVILLE, TENNESSEE, ASSIGNOR OF ONE-THIRD HIS RIGHT TO WILBUR F. FOSTER, OF SAME PLACE.

IMPROVEMENT IN 4BuueLM-AL'ARMS.

' Specilication forming part of Letters Patent No. 217,556, dated July 15, 1879 application filed May 26, 1879.

To all whom it may concern:

Be it known that I, AUSTIN P. SIMS, of

Nashville, in the county of Davidson and State lwhich will then spring down and explode a p percussion pellet or cap, and thus give alarm.

My burglar-alarm may be applied to a shutter opening either outward or inward, and my improvements enable me to set the plunger by means of a removable key, so that the shutter may be swung at will during the day, when Vdanger is not apprehended, without liability to explode the pellet, which may remain safely in place 5 and they also enable me to securely bolt the shutter automatically by the act of exploding` the 4pellet and giving alarm. In ordinary alarms of this class the projection from the plunger is not only employed to set the plunger, but it also projects from the case, so as to be struck to trip the plunger and cause alarm. Instead of this, I employ an eccentric tripper that is concealed below the plunger, which enables me to dispense with any permanent projection reaching outside of the alarm, and to use instead a short projection and the removable key merely for setting.

In the accompanying drawings, which illustrate my invention in a convenient form of embodiment which I prefer, Figure 1 is a perspective view of my burglar-alarm applied. Fig. 2 is a front elevation, partly in section. Fig. 3 is a vertical section on the line 3 of Fig. 2. Fig. 4 is a transverse section on the lines 4 4 of Figs. 2 and 3, and Fig. 5 is a section on the line 5 of Fig. 2.

A indicates the case, B the spring-plunger, and C an arm or projection on the upper end of the plunger, pro vided with a key-hole. This key- A hole may, it' desired, be of any peculiar form,

requiring the small key D, which I prefer to make of steel, to be shaped accordingly, so as to prevent the easy insertion of a nail or other substitute convenient to house -breakersg or small tumblers may guard the key-aperture, so as to require a peculiar key to enter it, as is well understood by lock-makers.

The ease A is shown as rectangular, though it may be circular or of any other form, and it is provided with an angular slot, E, in front, and a transverse slot, F, on one side, both being for the insertion of the key and the setting of the plunger.

which is designed to enter an aperture in a window-sill when the plunger is set, so as to present one of its extreme ends, g, to be struck by the wall of the aperture if the shutter is attempted to be swung.

A ledge, H, is provided 0n the interior of the case, upon which the arm C rests when the plunger is set for giving alarm, to support the plunger in position to be tripped.

' A loose clamp or pellet plate, K, is provided at the bottom of the slot E, under which the pellets are to be placed, so as to be clamped by the weight of the plate, as shown in Fig. 3, and prevented from getting out of place.

The operation is as follows: Referring to Fig. 3, it will be seen that the plunger is at its lowestpoint, its arm C having struck the pelletplate K and exploded the pellet under it, and the lower end of the plunger having projected fully into the aperture in the window-sill and firmly bolted the shutter. Now, to raise the plunger to'the position indicated in Fig. 1,v

the key is inserted in front and the plunger is lifted, and, when near the top ot' the slot E, is turned, and then raised and turned still farther, until the arm C projects into the slot F and rests there, in which position the key can be withdrawn and the shutter swung freely, the lower end of the plunger being entirely withdrawn from the aperture in the window-sill.

When it is desired to set the plunger in the position, as shown in Fig. 2, to be tripped and to explode the pellet, it is turned by the key part-way to the front, when it slips down by the force of its spring, so that the arm C rests on the ledge H and the eccentric Gr slightly enters the aperture in the sill. Any swinging of the blind in either direction will now cause one of the points g of the eccentric to impinge The lower end of the plunger is provided with an eccentric, G,

` 'against one of the sides of the sill-aperture and turn the plungerso as to disengage the arm C from the ledge H and let it down violently upon the pellet-plate. From this position it can, ot' course, be raised-to the position shown in Fig. 2.

The advantage of having a removable key to set the alarm is very great, because no projection is presented, as in other alarms, to be hit by accident, or to enable the burglar to take hold of it and manipulate the alarm so' spring-plunger having a short projection, and a bottom eccentric with a removable key fitting a keyway in the top projection, all substantially as described.

3. TheI combination ot' the case having the two slots, as described, the spring-plunger having the short projection, the ledge I-l, and the removable key, whereby the plunger may be set to allow the shutter to swing freely, or in a position for tripping, so as to bolt the shutter.

4. A combined burglar-alarm and automatic shutter bolt, substantially as described, `consisting of the case with its slots E F, the springplunger with its short arm C and eccentric Gr, the ledge H, the percussionpellet-holder plate K, and the removable key I).

In testimony whereof I have hereunto` subscribed my name.

' AUSTIN P. SIMS.

Witnesses:

B. A. PHILLIPS, VINET DoNELsoN. 

